# file an `at` job of running contents of 'file' at 12:05
open AT, "at -f test 1205 2>&1 |" || die "can't `at`";
while(<AT>) {
        ($job_id,$job_date,$job_time) = (/^job (\d+) at (\S+) (\S+)/);
+ 
} # last one seen wins

print "at job ID: $job_id\n";
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i had tried the above method recommended. However, when i run the code with the output append to a file. This doesn't work. the $job_id simply return a empty field. Why? Pls.. help..

It's probably a difference between Linux and Solaris `at` output - adjust the regexp accordingly.

hey, i had tried the above command in my perl script. however, it doesn't give me the value i want. instead, it return an empty values for all the 3 fields. WHY ?

Then your regexp is probably wrong. If you do this:

echo "ls" | at -f test 1205 >at.stdout 2>at.stderr
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(where 'test' is your example input file) then paste the contents of at.stdout and at.sterr here, we can figure out the applicable regexp for your system.